Using SMIL and Timing Charts in SVG Animations

The Synchronized Multimedia Integration Language (SMIL), which provides full control over the animation of SVG graphics without the need for JavaScript, stands out particularly because it can run inside `<img>` tags in HTML. However, because its structure requires a separate tag for every element and property—which can lead to code bloat—timing charts serve as an effective planning tool for managing SMIL animations.

The Structure of SMIL Animations and the Code Bloat Issue

Unlike CSS and JavaScript alternatives, SMIL does not allow you to list multiple properties simultaneously within a single keyframe. Each SMIL tag can target only a single element and just one property of that element. For example, if you want to change both the fill color and the opacity, you have to write separate `<animate>` tags. As animations become more complex, this causes the codebase to grow rapidly and become difficult to manage.

Animation Planning with Timing Charts

To prevent code clutter and make the process more manageable, visual planning tools known as "timing charts" can be used. Essentially acting as line segments, these charts allow you to clearly map out when animation components will start and end. When creating a chart, adding durations as labels rather than making full-scale drawings lightens the workload while preserving the relative timing between components.

Industry Implications and Use in Web Design

In today's web design landscape, where performance and lightweight assets are increasingly important, the combination of SVG and SMIL—which reduces reliance on JavaScript—remains relevant for modern interface developers. Planning complex animations with timing charts on paper or in a digital environment before writing any code both shortens development time and prevents unnecessary redundancies in the codebase.

*This report has been prepared based on data published by Smashing Magazine.